accretion disk


Definition of accretion disk

: a disk of usually gaseous matter surrounding a massive celestial object (such as a black hole) in which the matter gradually spirals in toward and accretes onto the object as a result of gravitational attraction

Examples of accretion disk in a Sentence

Recent Examples on the Web

This build up of matter on the edge of black holes are known as accretion disks. David Grossman, Popular Mechanics, "Supermassive Black Hole Spotted Sucking in Gas at a Third of Light Speed," 21 Sep. 2018 The researchers discovered that the star is forming from the center of a rotating disk of gas and dust, called an accretion disk, just like smaller stars such as the sun. Jay Bennett, Popular Mechanics, "Astronomers Catch Rare Sight of Incredibly Massive Star's Formation," 21 Aug. 2016 The calculated black holes also had accretion disks that glowed brightly. Chris Lee, Ars Technica, "Galaxy mergers hide ravenous supermassive black holes," 14 Nov. 2018 In these cases, matter from the star falls into its ultradense partner, and the swirling gas forms what's known as an accretion disk around the black hole's maw. National Geographic, "Thousands of Black Holes May Lurk at the Galaxy's Center," 4 Apr. 2018 Theorists suspected an unseen orbiting companion was sucking in material from the star, creating a superhot accretion disk blazing with x-rays. Adrian Cho, Science | AAAS, "Hawking’s final quest: saving quantum theory from black holes," 20 Mar. 2018 Somehow, the accretion disk of mostly hydrogen gas that surrounded the early sun coalesced into the rocky planets and asteroids in the solar system, and those protoplanets shed some elements in a process known as devolatilization. Jay Bennett, Popular Mechanics, "Scientists Create Most Accurate Estimate of Earth's Composition," 18 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'accretion disk.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of accretion disk

1972, in the meaning defined above

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The first known use of accretion disk was in 1972

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to boil down or concentrate

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